FY 2012 Recent Bering Sea warm and cold events in a 95-year context Overland, J.E., M. Wang, K.R. Wood, D.B. Percival, and N.A. Bond Deep-Sea Res. II, 65–70, 6–13, doi: 10.1016/j.dsr2.2012.02.013 (2012) The meteorology and oceanography of the southeastern Bering Sea shelf was recently dominated by a multi-year warm event (2000–2005) followed by a multi-year cold event (2007–2010). We put these recent events into the context of the 95-year air temperature record from St. Paul Island and with concurrent spatial meteorological fields. For March 2000–2005 the mean air temperature anomaly at St. Paul was 2.1 °C above the long-term mean, and for March 2007–2010 the mean temperature anomaly at St. Paul was 4.7 °C below the long-term mean. The only multi-year temperature deviations comparable to the first decade of the 2000s are a cold event from 1971 to 1976 followed by a warm event from 1978 to 1983. There was also a short warm event 1935–1937. The temperature transition between warm and cold events in the 1970s and 2000s took two years. While there are theoretical arguments for some physical memory processes in the North Pacific climate system, we cannot rule out that the recent warm and cold events are of a random nature: they are rare in the St. Paul temperature record, they are dominated by North Pacific-wide sea level pressure events rather than local Bering Sea processes, and they are consistent with a red noise model of climate variability. The 1970s transition appears to have an ENSO (El Niño–Southern Oscillation) influence, while the recent events are likely connected to Arctic-wide warming. Evidence provided by the 95-year St. Paul meteorological record reinforces the idea that a red-noise model of climate variability is appropriate for the North Pacific and southeastern Bering Sea. We stress the importance of relatively rare sub-decadal events and shifts, rather than multi-decadal variability associated with the Pacific Decadal Oscillation (PDO). Thus, in the future we can expect large positive and negative excursions in the region that can last for multiple years, but there is as yet little predictability for their timing and duration. Feature Publications | Outstanding Scientific Publications Contact Sandra Bigley | Help
